Sea Soul series, part 6

Pufferfish Secrets

Pufferfish swell to about three times their volume, eat with a beak of fused teeth, and one small species draws 2-metre circles in the sand.

White-spotted puffer resting on rocks on the seabed at Anilao, Philippines — Photo: Diego Delso, CC BY-SA 4.0, Wikimedia Commons

Part 6 of Sea Soul Secrets meets the pufferfish, the animal behind Puffy Cheek. National Geographic counts more than 120 species worldwide, from a 1-inch dwarf puffer to species up to 3 feet long.

The famous puff. When threatened, a puffer gulps water and pumps it into its stomach. The University of Texas Marine Science Institute says one spiny species, the balloonfish, swells to about 3 times its usual volume. The many folds in its stomach let the stomach stretch 50 to 100 times. Puffers have no ribs or pelvis, so a flexible spine can curve over the full stomach while hundreds of sharp spines stand up.

A beak for a mouth. All pufferfish have four teeth fused together into a beak-like shape, National Geographic explains.

A strong toxin. Pufferfish can carry tetrodotoxin, which National Geographic describes as up to 1,200 times more poisonous than cyanide, with enough in one fish to kill 30 adults and no known antidote. In Japan, where the fish is called fugu, only trained, licensed chefs may prepare it.

An artist on the seabed. Researchers at Osaka University studied a pufferfish about 10 cm long. It builds a circle about 2 metres across on the sea floor. Deep ditches run out like the spokes of a wheel around the outer ring, with a maze of shallow ditches in the middle. The circle is a nest for attracting a female, and the fish digs its ditches in straight lines, working from the outside in.

Meet Puffy Cheek in the Sea Soul collection.